The trailer for Godzilla vs. Kong has arrived, pitting the King of the Monsters against Skull Island's protector and one of his greatest opponents. However, although the trailer shows a mysteriously enraged Godzilla wreaking havoc on the world, viewers were quick to notice the promo may be hiding the movie's real villain. What's more, Godzilla vs. Kong's rumored threat -- the MonsterVerse version of Mechagodzilla -- could be far deadlier than anything the Titans have faced in the franchise before.
Created in the 1970s, Mechagodzilla was designed to present a more serious danger to Godzilla and was partly inspired by the popular mecha (or robot) anime and manga genre. The character made their debut during the Shōwa period of Godzilla films in 1974's Godzilla vs. Mechagodzilla, in which Mechagodzilla was a weapon engineered by a race of alien invaders known as the Simians. This version of the Kaiju had multiple missile launchers and could fire energy beams from its eyes and chest. It was also capable of going toe-to-toe with Godzilla and nearly beat him during their first battle in the film.
Intriguingly, the Shōwa Mechagodzilla was initially equipped with a layer of fake flesh, allowing it to pretend to be the real Godzilla until the actual King of the Monsters showed up. The popular theory is the MonsterVerse will carry over that element for its version of Mechagodzilla, which would explain why a creature that appears to be Godzilla is "cutting a swath of destruction across the globe," as the Godzilla vs. Kong synopsis puts it. What's more, it's speculated the film will combine this aspect with the backstory for the Heisei era Mechagodzilla, in which the creature was built by by the United Nations Godzilla Countermeasures Center.
Mechagodzilla has been heavily rumored to appear in the MonsterVerse since January 2020, when a Godzilla vs. Kong toy leak revealed an action figure for the Kaiju. On top of that, there's a brief shot in the Godzilla vs. Kong trailer showing a city being attacked by a metallic being that looks a whole lot like Mechagodzilla, down to its signature glowing eyes. A separate shot from the trailer similarly shows Ren Serizawa, a character who's believed to be the son of the late Monarch scientist Ishirō Serizawa from the other MonsterVerse Godzilla films, standing in front of multiple screens, including one that reads "maximum charge".
Add it all together and the implication is Ren Serizawa is part of an organization that built and controls Mechagodzilla, presumably in response to the Titans being reawakened and roaming the Earth freely at the end of Godzilla: King of the Monsters. That movie also included a post-credits scene in which Alan Jonah and his eco-terrorist group recovered one of King Ghidorah's severed heads, which may have provided the regenerative genetic substance used to create Mechagodzilla's pseudo-flesh in Godzilla vs. Kong. That would mean humankind is as much the true threat in the movie as this new iteration of Mechagodzilla.
The idea of humanity being the real villain has long been a core theme of the MonsterVerse, going back to Godzilla (2014) revealing the atomic bombing tests in the 1950s were humankind's attempts to kill Godzilla. Kong: Skull Island continued to develop the idea by having members of the U.S. Army try and kill Kong during the expedition to Skull Island, in retaliation for Kong attacking when they began dropping seismic explosives on his home. Mankind's attempts to tame nature backfiring on them was once again a theme in King of the Monsters, which presented the idea of Titans attacking humanity as a parable for climate change.
Point being, a version of Mechagodzilla engineered by people to try and control the Titans would once more bring these issues to the foreground in Godzilla vs. Kong. This would subsequently allow the film to build on the events from the other MonsterVerse movies both thematically and narratively, which would only make sense for a crossover that could end up marking the culmination of the franchise.